Automatic inertia-type switch mechanism



Dec. 27, 1960 w. E. CUNNINGHAM 2,966,564

AUTOMATIC INERTIA-TYPE SWITCH MECHANISM Filed Aug. 18, 1959 INV ENTORUnited States Pgnt AUTOMATIC INERTIA-TYPE SWITCH MECHANISM William E.Cunningham, 111 S. Central Ave., Visalia, Calif.

Filed Aug. 18, 1959, Ser. No. 834,529

2 Claims. (Cl. 200-61.46)

My invention relates to a new type of switch mechanism that will be ofgreat value when used in connection with caution or warning lights towarn of deceleration of a mechanism and particularly to an inertia typeswitch mechanism to be used in connection with caution lights on therear of a moving vehicle to warn of deceleration of the said vehicle, inwhich the inertia of a rapidly rotating ywheel closes an electricalcontact when deceleration occurs and the flywheel tends to drive theshaft on which it is located.

With the advent of more, speedier cars and improved highways, more andmore attention is being given to the problem of trac safety. With movingvehicles travelling at high rates of speed on crowded highways, anydeceleration on the part of one, without any warning to those followingcould cause trouble if the deceleration of the said vehicle was notimmediately noticed by operators of the following vehicles.

An object of my invention is to provide an automatic switch mechanismthat will automatically close the circuit of a caution light on the rearof a moving vehicle when that vehicle is decelerating.

Another object of my invention is to provide an automatic switchmechanism that will put the caution lights into operation without anyconscious effort on the part of the operator of the deceleratingvehicle.

Another further object of my invention is to provide an automatic switchmechanism, which, after having closed the circuit to a caution lightsystem with deceleration of the moving vehicle, will again automaticallybreak the circuit to the said lighting system as soon as steady motionis attained or accelerating motion is again resumed.

Another further object of my invention is to provide an automatic switchmechanism for caution lights on the the rear of a moving that willautomatically open and close the circuit to the said lights without anyconscious effort on the part of the operator of the vehicle employingsuch lights at times when deceleration is sudden without the applicationof brakes which would close the circuit to the red stop lights.

In the accompanying drawing I show the novel features which I believe tobe characteristic of my invention, both as to its manner of organizationand mode of operation and which will be better understood from thefollowing description when read in conjunction with the followingdrawing in which The single gure shows an isometric view of alongitudinal section through the middle of the rotating shaft of theswitch mechanism.

Referring now to the drawing in which the same reference numeralsindicate the same elements, the base 2 serves as a support for the otherparts and provides a suitable mounting piece for the device. The endhousings 3 attached to the ends of the base 2 so as to be easilyremoved, have near their centers extensions 4 to provide more supportfor the bronze bushings 5 which provide bearing surfaces internally forthe shaft 6, part of which is shown in section. The remainder of thehousing, made of one piece 7, lits into a rabbet in the two sides andend pieces and is attached to the base so as to be easily removed.

On the threaded end of shaft 6 a short distance is of reduced diameterto provide a shoulder as a stop for the V-belt pulley 8 when nut 9 isscrewed tightly against said pulley. Internal of the housing, on shaft 6are the following parts: a contact arm 10 made of copper or brass of twoparts clamped together around the said shaft by means of machine screws11; a small flywheel 12 tightly secured internally to the outer race 13of a ball bearing assembly 14, the inner race of which is ytightlyrfitted on shaft 6, and bearing near its periphery 0n the side facingthe contact arm, four pins of suitable length, spaced degrees apart,with two opposite ones 15 insulated from the said flywheel to serve ascontact points and the other two opposite ones 16 in contact with thesaid flywheel to serve as driving pins; and a cylindrical commutator 17insulated from said shaft 6 yet rigidly fitted to it so as to rotatewith it, with two flexible electrical connectors 18 from diametril callyopposite points on the side of the said commutator to the two saidcontact pins 15.

Electrical contact with the rotating commutator 17 is made through acarbon brush 19 which slides in a nonconductor brush holder 20 and isheld in sliding contact with the said commutator 17 by a smallcompression spring 21 which also serves to conduct the electricalcurrent to the brass cap and terminal 22. A wire from terminal 22 wouldgo to one contact point of the bulb of a caution light while anotherwire would continue the circuit from the other contact point of the saidbulb to a live terminal of the fuse block. The circuit would becompleted through the grounded base 2.

The operation of the switch mechanism is as follows: As long as thepower source is driving the shaft 6, the contact arm will be in contactwith the driving pins 16 and will rotate the flywheel 12 in a clockwisedirection. Since pins 16 are not electrical contact pins, the electricalcircuit remains broken and the caution lights will remain off. If thedriving power source, the engine, decelerates, the inertia of therotating flywheel forces the said iiywheel forward, clockwise, until thecontact pins 15 are brought into contact with the Contact arm 10 thusclosing the electrical circuit to the caution lights causing them to goon. As long as deceleration continues, the lights will remain; but, assoon as steady speed is maintained or acceleration begins, contact isbroken, and the caution lights go off. The action is completelyautomatic, and requires no effort on the part of the operator. Anautomatic switch mechanism of this type used in connection with yellowcaution lights on the rear of moving vehicles will be of great value inpreventing rear-end collisions due to sudden deceleration without use ofbrakes.

While I have described and illustrated particular embodiments of myinvention, modifications which are within the scope of my invention mayoccur to those skilled in the art; so I desire that it be understood,therefore, that all such modications are included within the scope ofthe claims annexed to and forming a part of this application.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

l. An inertia-type automatic switch mechanism, that will close anelectric circuit to caution lights whenever deceleration of its drivingsource is taking place, cornprising a suitable housing and mounting basefor securing said device in operating position; a rotatable shaft, withbearings in the ends of the said housing, one end of which extendsoutside the end of the said housing to accommodate a suitable beltpulley or other driving means; a ywheel mounted on the said shaft withinthe said housing with a ball bearing assembly between the said flywheeland the said shaft; a ring commutator on said rotatable shaft a shortdistance away from the said flywheel insulated from the said shaft yetfirmly secured to said shaft so as to rotate with it; four metal pins orpegs through the said flywheel spaced 90 degrees apart near theperiphery of the said flywheel with two of the said pegs, opposite eachother, insulated from the said flywheel to serve as electrical contactpoints, and the other two in contact with the said flywheel to serve asdriving pins; a contact arm of brass or other conductor metal attachedfirmly to and making good electrical contact with the said rotatableshaft on the side of the said flywheel away from the said commutator,the length of which is equal to or slightly less than the diameter ofthe said flywheel, so positioned that it will be in contact with thedriving pins when the said rotatable shaft is turning the said flywheeland in contact with the said insulated contact pins when deceleration istaking place and the inertia of the said flywheel forces the saidilywheel forward to tend to drive the said rotatable shaft; two flexiblewire conductors from diametrically opposite points on the side of thesaid ring commutator to the adjacent ends of the two said contact pointsin the said ywheel; a carbon brush in suitable non-conductor mount heldin contact with said commutator by a compression spring which serves aselectrical conductor between said carbon brush and brass terminalmounted on but insulated from the top of the said housing.

2. An automatic inertia-type switch mechanism as set forth in claim 1for use in connection with a caution light or lights to warn ofdeceleration of the power source driving the said switch mechanism andparticularly for use in connection with caution lights on the rear ofmoving vehicles, whose operation is dependent upon the inertia-notcentrifugal force-of a rapidly rotating ilywheel so positioned in theelectrical circuit of the said vehicle that, as long as the power of themoving vehicle is driving the said flywheel, the circuit remains brokenand the caution lights remain off; but as soon as the driving shaftdecelerates, the inertia of the said rapidly rotating flywheel causesthe said flywheel to move clockwise on the said ball bearing assemblyand bring the said electrical contact pins in contact with said contactarm thereby closing the said electrical circuit and lighting the saidcaution lights.

References Cited in the ille of this patent UNITED STATES PATENTS2,811,597 Havelka Oct. 29, 1957

